Field of the Invention
The invention relates to a microphone device, more particularly relates to a microphone device capable of canceling far field noise.
Description of Related Art
Along with the continuous improvement of technology, all of electronic products have been developed with a tendency to become lighter and more miniaturized, and the electronic products like smartphone, tablet computer, or notebook, etc., have become indispensable in daily life of human beings. For each of those aforementioned electronic products, in order to allow a user/listener to listen to the audio information provided by the electronic product without disturbing the other people around, an earphone has become a necessary accessory to the electronic product. Otherwise, in order to make a phone call by using the electronic products, a headset having a microphone is also a popular accessory.
In order to perform both audio listening and sound collecting functions, a conventional headset adopts a design having an earphone and a microphone separated from each other, the earphone and the microphone are connected to each other via a signal wire or a simple structure. Therefore, the earphone is close to the ear, and the microphone is close to the mouth. However, the microphone in the above-mentioned design also receives the environmental noise, so the distinctness of the voice of the user is greatly affected. Generally speaking, the microphone has been improved both in sound-receiving efficiency and stability, and can provide clear and fluent voice quality either in a noisy environment or in high-speed movement. However, since a diaphragm for reception is a plane, phase noises are caused. That is to say, sound generated by a sounder and surrounding environmental noises may be heard by a receiver together, which interferes in the understanding of an audio message by the receiver.